The invention relates to an ostomy bag, and in particular to a vented bag with a gas filter.
Ostomy bags incorporating gas filters are known and examples are described in GB 2 116 433 and EP 0 852 936.
The first of these earlier patent documents, GB 2 116 433, describes an ostomy bag having two outer walls, one intermediate wall and two chambers. The ostomy-receiving opening is provided in one outer wall, a gas vent is provided in the intermediate wall and a gas passage is provided in the second outer wall which is also fitted with a gas filter. The upper portion of the intermediate wall is embossed to help prevent the various walls sticking together and inhibiting gas flow.
The second of these earlier patent documents, EP 0 852 936, describes an ostomy bag having two outer walls, one full and one partial intermediate wall, and two chambers. The partial intermediate wall is located in the upper portion of the second chamber. The ostomy-receiving opening is provided in the first outer wall, gas vent is provided in the full intermediate wall and a gas passage is provided in the other outer wall which is also provided with a gas filter.
One of the problems experienced by users of vented ostomy bags with gas filters is the blocking of the gas filter by solids or liquids. The division of the ostomy bags into two chambers and the provision of complex gas paths through the bags to the filter are attempts to reduce the occurrence of this problem. However, the known products are not completely successful at overcoming the problems described.